Can Butterbur Fight Migraines?

If you suffer from migraine headaches. you may be searching for an effective treatment, or better yet, a preventive. Conventional medicines often fail to relieve the debilitating pain or head off new attacks, and many people turn to alternative/complementary practices, including herbal remedies.

One herb that has some research behind it is butterbur root (Petasites hybridus), a shrub-like plant in the daisy family, native to Europe, North Africa and Southwestern Asia. Also called purple butterbur, its extracts have been used to treat migraines in Europe for decades. Butterbur is sold in the U.S. under the trademark Petadolex (developed in Europe), though many other butterbur products are available from other supplement makers. There may be real benefits to butterbur—but there are also some caveats.

What the research shows

A few clinical trials suggest that butterbur may decrease the frequency, duration and intensity of migraines. For example, in a study of more than 200 migraine sufferers,published in Neurology in 2004, those who took 150 milligrams a day ofPetadolex in split doses for four months reported a 48 percent decrease in frequency of headaches. Those who received a placebo reported a 26 percent decrease in headache frequency. Another paper that year, in European Neurology, found reduced frequency of migraines in people taking a lower dose (100 milligrams) for three months. Butterbur may also be effective in children, according to a 2007 study published in the European Journal of Pain.

Several professional groups discuss butterbur as a potential migraine preventive. The American Academy of Neurology classifies it as an effective drug for this use. And the Natural Standard, which evaluates complementary and alternative therapies, gives butterbur a “B,” saying there is “good scientific evidence” behind it. Still, these and other experts cite the need for more studies and concern about the lack of long-term safety data.

When taken regularly, the herb is thought to reduce migraine attacks by inhibiting pro-inflammatory substances in the body and by reducing spasms in the smooth muscle of blood vessel walls in the brain. There’s no evidence that it helps after a migraine develops or that it helps with other kinds of headaches.

Before you butter up

Butterbur may cause mild intestinal symptoms—mostly burping, but also nausea and stomach pain. Of more concern, naturally occurring chemicals in butterbur called pyrrolizidine alkaloids are toxic to the liver and have been found to cause cancer in lab animals. They must be processed out to make the supplement safe. Petadolex is made in Germany, where it’s regulated as a drug by the government; it is purified to contain no detectable levels of alkaloids. But you can’t be sure about other butterbur products, even if they claim to be free of alkaloids.

You shouldn’t use butterbur if you are pregnant or nursing or if you are allergic to related plants including daisies, marigolds, ragweed and chrysanthemums. Interactions with calcium channel blockers and some other drugs taken for heart disease are theoretically possible—though none have been reported.

Bottom line: If you get migraines, and conventional preventive strategies haven’t worked, butterbur may be worth a try. Petadolex is the safest option. If you see no improvement within four to six months, stop taking it. A month’s supply is not cheap—it costs about $50.